Since light emitting diodes (LEDs) have many positive attributes such as high reliability, relatively long lifespans, relatively low maintenance costs, and relatively low power consumption, LEDs may contribute to reductions in energy usage. Further, as illumination devices, LEDs may be usefully used while having various designs applied thereto and generating relatively low levels of heat.
Phosphor materials used in devices including the LEDs as described above or the like are materials converting specific wavelengths of light provided from various light sources into wavelengths of light required thereof, and have been recognized as a core technology in the forming of white LEDs. In addition, phosphor material efficiency acts as a principal factor directly relevant to efficiency in light source products including display devices, simultaneously with being necessary for driving display devices. Recently, research into a technology for implementing white light having properties close to those of natural light has been making progress and research into white LED devices for emitting such white light has been actively conducted.
In general, white LEDs have been manufactured in a scheme in which at least one or more phosphors selected from red phosphors, blue phosphors, yellow phosphors and the like are applied to blue or ultraviolet LED chips. For example, when red phosphors are combined with phosphors exhibiting a different color in the case of the use thereof, in a case in which a full width at half maximum of a respective phosphor is relatively low, it may be difficult to secure a sufficient color rendering index. Further, there may be limitations in implementing white light having required properties, close to those of natural light.
In addition, in the case of red phosphors according to the related art, a full width at half maximum thereof has a relatively low level, and a light emission peak is provided within a light wavelength band of 550 to 700 nm such that it may be difficult to exhibit a sufficient color rendering index. Therefore, the development of red phosphors capable of implementing a sufficient color rendering index while having high light emission efficiency has been in demand.